1
Japanese spider crab
![Images © Chris Philpott/BBC Focus](https://c02.purpledshub.com/uploads/sites/41/2018/07/TopTen_SpiderCrab_Finaluse-c6b4118.jpg?webp=1&w=1200)
Leg span: 4m
Distribution: Pacific Ocean around southern Japan
2
American lobster
![Images © Chris Philpott/BBC Focus](https://c02.purpledshub.com/uploads/sites/41/2018/07/TopTen_Lobster_Finaluse-8d6b489.jpg?webp=1&w=1200)
Length: 1m
Distribution: Atlantic Ocean around North America
3
Coconut crab
![Images © Chris Philpott/BBC Focus](https://c02.purpledshub.com/uploads/sites/41/2018/07/TopTen_CoconutCrab_Finaluse-8d6b489.jpg?webp=1&w=1200)
Leg span: 1m
Distribution: Indian Ocean and Central Pacific Ocean
4
Tasmanian monster crab
![Images © Chris Philpott/BBC Focus](https://c02.purpledshub.com/uploads/sites/41/2018/07/TopTen_TasmanianCrab_Finalu-b2a7a36.jpg?webp=1&w=1200)
Leg span: 80cm
Distribution: Oceans off southern Australia
5
Tasmanian giant freshwater crayfish
![Images © Chris Philpott/BBC Focus Images © Chris Philpott/BBC Focus](https://c02.purpledshub.com/uploads/sites/41/2018/07/TopTen_Crayfish_Finaluse-93d5755.jpg?webp=1&w=1200)
Distribution: Rivers and streams in Tasmania
6
Zebra mantis shrimp
![Images © Chris Philpott/BBC Focus](https://c02.purpledshub.com/uploads/sites/41/2018/07/TopTen_Mantis_Finaluse-2a85815.jpg?webp=1&w=1200)
Length: 40cm
Distribution: Indo-Pacific region
7
Alicella gigantea
![Images © Chris Philpott/BBC Focus](https://c02.purpledshub.com/uploads/sites/41/2018/07/TopTen_Alicella_Finaluse-b16d997.jpg?webp=1&w=1200)
Length: 34cm
Distribution: Kermadec Trench, New Zealand
8
Giant tiger prawn
![Images © Chris Philpott/BBC Focus](https://c02.purpledshub.com/uploads/sites/41/2018/07/TopTen_Prawn_Finaluse-b16d997.jpg?webp=1&w=1200)
Length: 33cm
Distribution: Indian Ocean and West Pacific
9
Giant acorn barnacle
![Giant acorn barnacle © Chris Philpott/BBC Focus](https://c02.purpledshub.com/uploads/sites/41/2016/07/Giant-acorn-barnacle-ffdef04.jpg?webp=1&w=1200)
Length: 30cm
Distribution: Coast of northwest America
10
Euphausiid (krill)
![Euphausiid (krill) © Chris Philpott/BBC Focus](https://c02.purpledshub.com/uploads/sites/41/2016/07/TopTen_Krill_Finaluse-9eee9a8.jpg?webp=1&w=1200)
Length: 15cm
Distribution: Antarctic Ocean
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